Farmers, foragers and human skulls

Agriculture played a role in the shape, form and size of human skulls, researchers find

Thousands of years ago, the diets of humans during the transition to farming affected skull shape, according to David Katz, a postdoctoral researcher at the University of Calgary.

Katz, along with a team of researchers at the University of California-Davis, examined 559 crania and 534 lower jaws to determine the effect that diet had on skull shape and size, according to a university release.

“The youngest skulls in my farmer sample are about 6,000 to 7,000 years old,” Katz said in an interview with Farms.com on Friday.

“Most of the remains from older populations are too fragmentary to incorporate into a study like the one we undertook,” he said, noting that the transition to farming began around 11,000 years ago.

The results showed that both diet and climate have affected the structure of humans today, he said.

“The effect of farming is mostly visible in the areas of the skull that generate or experience stress during chewing. The simplest explanation is that these stresses were reduced (in farmers) because farming diets were generally softer (than those of foragers and hunters).”

Unlike hunters and foragers, farmers tended to consume foods that had lower masticatory demands, such as dairy, according to an article in the Proceedings of the National Academy of Sciences. As a result, farmers had reduced and repositioned chewing muscles.

“The maxilla, or upper jaw, is shorter from front to back in farming groups,” Katz said. “Also, the mandible, or lower jaw, is smaller.”